Protective masking solutions comprising thixotropic film formers

ABSTRACT

This invention provides a masking material that can be used to protect an underling surface (e.g., an automobile surface) during an overcoating (e.g., painting) operation. The masking material in one embodiment includes a thickener and a pH control agent and water. The masking material can be applied to a surface that is to be protected from paint overspray or other coating processes, allowed to dry, and the surface then coated (e.g., with paint). After drying of the paint, or other coating, the masking material can removed by water washing.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit of and priority to U.S. Ser. No.60/474,720, filed on May 30, 2003 which is incorporated herein byreference in its entirety for all purposes.

STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSOREDRESEARCH AND DEVELOPMENT

[Not Applicable]

FIELD OF THE INVENTION

The present invention relates to the field of protective coatings to beused during coating operations of various surfaces including surfaces ofvehicles or buildings. In certain embodiments the invention provides animproved method and composition for masking selected portions of asurface, in particular a painted vehicle surface, from paint or otherovercoating materials.

BACKGROUND OF THE INVENTION

It is well known that painting, or other overcoating operations oftenrequire masking of certain portions of the surface of the object to bepainted to prevent overspray by the coating material (e.g., paint). Forexample, it is often necessary to mask trim, and/or windows, and/orcertain already painted areas on a vehicle (e.g., a motor vehicle) or acomponent of a vehicle (e.g., a door, a bumper, a frame, etc.) frompaint overspray.

Similarly, when painting building components (e.g., window frames) it isoften desirable to protect certain areas (e.g., the glass windows) ofthe building components from paint overspray.

On occasion, it is necessary to mask painted portions of a vehicle orbuilding from paints of a different color and overspray of paints of thesame color. In addition, it is often desired to protect the surfaces(e.g., floors or walls) of the area (e.g., paint spray booth) in whichthe overcoating (e.g., painting) operation is performed.

In practice, masking operations are often one of the most time consumingand, therefore, expensive parts of the painting/overcoating process. Inspite of attempts to develop suitable chemical masks for vehiclepainting, vehicle painters continue to use primarily masking tape andpaper to cover portions of a vehicle where paint is not desired. To maskthe trim on a car, for example, will often require many hours of tediouslabor. Furthermore, even when done carefully, defects in such paintmasks allow paint to contact surfaces that are desired to be protected.

Chemical masking solutions have been proposed to the problem ofprotecting surfaces during coating processing operations. However, suchtechniques have often not found extensive use. Some of the proposedchemical masks have been unsuitable for application to portions of avehicle or building because of damage that could potentially occur tothe protected portions of the vehicle or building. Other compositionsare not water-soluble which increases the difficulty and expense ofremoval. In addition, masks that require solvents for removal areproblematic in view of the increasing regulation of disposal of solventsas environmental regulation becomes stricter with time. Othercompositions are difficult to apply, difficult to remove, excessivelycostly, or the like.

From the above it is seen that an improved masking that is easilyapplied and removed, that provides good surface protection, that iseconomical, and whose use entails little or no environmental impact isneeded.

SUMMARY OF THE INVENTION

The present invention provides improved methods and compositions forprotecting a s vehicle (e.g., motor vehicle) or other surface subject toa coating operation such as painting, or for protecting a surface of anarticle manufacture during an assembly operation. In certainembodiments, the compositions comprise a thickener and a pH controlagent.

In one embodiment, this invention provides a method of temporarilyprotecting a surface in a coating (e.g., painting) operation. The methodtypically involves applying a masking material to the surface (e.g., thesurface of a vehicle), the masking material, before drying, comprisingan aqueous solution of: a thixotropic thickener present in an amountranging from about 0.15 to about 5 weight percent active ingredient anda pH control to adjust pH of the masking material from about pH 7.5 toabout pH 9.5; coating all or a portion of the surface with anovercoating compound (e.g., paint) where the masking material preventsthe coating compound from contacting the surface covered with themasking composition; and c) removing the masking material from thesurface whereby the coating compound applied to the surface covered withthe masking material is removed together with the masking material. Incertain embodiments, the coating is performed before the maskingmaterial is dried, while in certain other embodiments, the coating isperformed after the masking material is dried. In certain embodiments,the surface is a painted surface of an automobile and/or a bumper ortrim of a vehicle. In certain embodiments, the thixotropic thickener isa thickener selected from the group consisting of CarbopolTM EP-1, andAlbucril ESP. In various embodiments, the pH control comprises a base(e.g., sodium hydroxide, potassium hydroxide, magnesium hydroxide, anamine, sodium bicarbonate, etc.). The masking material can, optionally,further comprise a surfactant. The surfactant when present, it typicallypresent in an amount effective to produce a coating that lays outsmoothly in a substantially continuous film of the painted surface of anautomobile. In various embodiments surfactant is present at less thanabout 1 weight percent active ingredient of the masking material. Invarious embodiments the surfactant comprises a non-ionic surfactant(e.g., an alcohol ethoxylate). In certain embodiments, the surfactantcomprises TOMADOL™ 91-6 and/or TRITON™ DF-16. The masking material can,optionally, further comprise a viscosity control. Suitable viscositycontrols include, but are not limited to various salts (e.g., sodiumsulfate). In various embodiments the viscosity control ranges up toabout 2.0 weight percent active ingredient of the masking material. Themasking material can, optionally, further comprise an alcohol (e.g. astraight chain alcohol). In various embodiments the alcohol, whenpresent, is ethanol, methanol, and/or propanol. In various embodimentsthe alcohol is present in a concentration ranging up to about 20 weightpercent active ingredient of the masking material. The composition canalso, optionally, further comprise a biocide (e.g. Kathon LX 14) and/ora humectant (e.g. polyethylene glycol). In certain embodiments, thebiocide ranges up to about 0.2 weight percent active ingredient of themasking material. The composition can also, optionally, further comprisea flash corrosion inhibitor (e.g., ammonium benzoate). In variousembodiments the flash corrosion inhibitor comprises up to about 0.01weight percent active ingredient of the masking material.

In certain preferred embodiments, the masking material furthercomprises: a surfactant; a flash corrosion inhibitor; a viscositycontrol; an alcohol; and a humectant. In various embodiments thethixotropic thickener ranges from about 0.1 to about 10 weight percentactive ingredient of the masking material; the pH control is sufficientto set the pH of the masking about pH 7.5 to about pH 9.5; thesurfactant comprises less than about 1 weight percent active ingredientof the masking material; the flash corrosion inhibitor comprises fromabout 0 to about 0.2 weight percent active ingredient of the maskingmaterial; the viscosity control comprises a salt ranging from about 0 toabout 2 weight percent active ingredient of the masking material; thealcohol comprises from about 0 to about 20 weight percent activeingredient of the masking material; and the humectant comprises fromabout 0 to about 5 weight percent active ingredient of the maskingmaterial. In one embodiment, the thixotropic thickener is EP-1; the pHcontrol is sodium hydroxide; the surfactant is a nonanionic surfactant;the flash corrosion inhibitor is ammonium benzoate; the viscositycontrol agent is sodium sulfate; the alcohol is ethanol; and thehumectant is polyethylene glycol. In certain embodiments, thethixotropic thickener ranges from about 1 to about 2 weight percentactive ingredient of the masking material; the pH control is sufficientto set the pH of the masking about pH 8.5 to about pH 9.5; thesurfactant comprises less than about 0.5 weight percent activeingredient of the masking material; the flash corrosion inhibitorcomprises less than about 0.01 weight percent active ingredient of themasking material; the viscosity control comprises less than about 0.15weight percent active ingredient of the masking material; the alcoholcomprises less than about 0.4 weight percent active ingredient of themasking material; and the humectant comprises less than about 0.15weight percent active ingredient of the masking material.

This invention also provides a masking composition for the temporaryprotection of a surface during a coating procedure. The maskingcomposition typically comprises an aqueous solution of: a thixotropicthickener present in an amount ranging from about 0.15 to about 5 weightpercent active ingredient of the masking composition; and a pH controlto adjust pH of the masking composition from about pH 7.5 to about pH9.5. In certain embodiments, the thixotropic thickener is a thickenerselected from the group consisting of CARBOPOL™ EP1, and Albucril ESP.In certain embodiments, the pH control comprises a base (e.g., sodiumhydroxide, potassium hydroxide, magnesium hydroxide, an amine, sodiumbicarbonate, etc.). In various embodiments the masking compositionfurther comprises a surfactant (e.g., a surfactant present in an amounteffective to produce a coating that lays out smoothly in a substantiallycontinuous film of the painted surface of an automobile). In variousembodiments, the surfactant is present at less than about 1 weightpercent active ingredient of the masking material. In variousembodiments the surfactant comprises a non-ionic surfactant (e.g.alcohol ethoxylate). In one embodiment, the surfactant comprisesTOMADOL™ 91-6 and/or TRITON™ DF-16. The masking composition canoptionally further comprise a viscosity control (e.g., a salt such assodium sulfate). In various embodiments the viscosity control ranges upto about 2.0 weight percent active ingredient of the maskingcomposition. In certain embodiments, the masking composition furthercomprises an alcohol (e.g., a straight chain alcohol such as ethanol,methanol, and/or propanol). In various embodiments the alcohol can bepresent in a concentration ranging up to about 20 weight percent activeingredient of the masking material. A biocide (e.g., Kathon LX 14) canalso be included in the composition. In certain embodiments, the biocideranges up to about 0.2 weight percent active ingredient of the maskingcomposition. In certain embodiments, the masking composition furthercomprises a humectant (e.g., polyethylene glycol). In certainembodiments, humectant ranges up to about 5 weight percent activeingredient of the masking composition. In certain embodiments, themasking composition further comprises a flash corrosion inhibitor (e.g.ammonium benzoate). In various embodiments the flash corrosion inhibitorcomprises up to about 0.01 weight percent active ingredient of themasking composition. In certain embodiments, the masking materialcomprises: a thixotropic thickener; a pH control; a surfactant; a flashcorrosion inhibitor; a viscosity control; an alcohol; and a humectant.In certain embodiments, the thixotropic thickener ranges from about 0.1to about 10 weight percent active ingredient of the masking composition;the pH control is sufficient to set the pH of the masking about pH 7.5to about pH 9.5; the surfactant comprises less than about 1 weightpercent active ingredient of the masking composition; the flashcorrosion inhibitor comprises from about 0 to about 0.2 weight percentactive ingredient of the masking composition; the viscosity controlcomprises a salt ranging from about 0 to about 2 weight percent activeingredient of the masking composition; the alcohol, when present,comprises from about 0 to about 20 weight percent active ingredient ofthe masking composition; and the humectant comprises from about 0 toabout 5 weight percent active ingredient of the masking composition. Invarious embodiments the thixotropic thickener is EP-1; the pH control issodium hydroxide; the surfactant is a nonanionic surfactant; the flashcorrosion inhibitor is ammonium benzoate; the viscosity control agent issodium sulfate; the alcohol is ethanol; and the humectant ispolyethylene glycol. In various embodiments the thixotropic thickenerranges from about 1 to about 2 weight percent active ingredient of themasking composition; the pH control is sufficient to set the pH of themasking about pH 8.5 to about pH 9.5; the surfactant comprises less thanabout 0.5 weight percent active ingredient of the masking composition;the flash corrosion inhibitor comprises less than about 0.01 weightpercent active ingredient of the masking composition; the viscositycontrol comprises less than about 0.15 weight percent active ingredientof the masking composition; the alcohol comprises less than about 0.4weight percent active ingredient of the masking composition; and thehumectant comprises less than about 0.15 weight percent activeingredient of the masking composition.

This invention also provides kits for temporarily protecting a surface.The kits typically comprise a container containing a masking material asdescribed herein, and, optionally, instructional materials teaching theuse of the masking composition for temporarily protecting a surfaceduring an overcoating operation or during mechanical handling.

This invention also provides advertising materials comprising an audioor audiovisual presentation teaching the use of a container containing amasking material as described herein. In various embodiments where theaudio or audiovisual presentation comprises a medium selected from thegroup consisting of an audio tape, a compact disk, a video tape, a DVD,a view master, a slide show, an mpeg file, and a powerpointpresentation.

In certain embodiments, this invention also provides an article ofmanufacture comprising one or more surfaces coated with a maskingcomposition as described herein. In certain embodiments, the article ofmanufacture is an automobile or a component of an automobile.

Definitions

The term “aqueous solution” need not require the components comprisingthe solution actually be in solution phase (i.e. fully dissolved inwater). The term “aqueous solution” thus includes aqueous mixtures,aqueous suspensions, aqueous dispersions, and the like.

The terms “masking material” and “masking composition” are usedinterchangeably to refer to a composition that can be applied to asurface to protect that surface from overcoating (e.g., with paint) andthen subsequently removed from that surface (e.g., by washing/rinsingwith water).

The term “thixotropic” as used herein refers to an decrease in apparentviscosity of a material as the shear rate of the material increases.Typical thixotropic materials experience a reduction in viscosity whenshaken, stirred, or otherwise mechanically disturbed (i.e. brushing orrolling), but recover their original rheology in time, eventuallyreaching their original viscosity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates certain embodiments of the formulation of the presentinvention.

DETAILED DESCRIPTION

The present invention provides improved methods and compositions forprotecting a s vehicle (e.g., motor vehicle) or other surface subject toa coating operation such as painting, or for protecting a surface of anarticle manufacture during an assembly operation. For example, in oneembodiment, certain regions of an automobile, or other surface, may bemasked using the coating compositions of the present invention toprotect those regions from paint overspray in a painting booth. Inanother embodiment, an article of manufacture (e.g., an automobilepanel) may be protected from mechanical impact and/or abrasion by thepresence of such an overcoating.

In addition it is also often desired to protect the surfaces of the areain which an overcoating operation (e.g., painting) is performed. Inparticular, it is desired to protect the walls, floors and othersurfaces of such an area (e.g., a painting booth) from paint oversprayand spills. In addition, it is also desirable to reduce airborne dust insuch areas during overcoating operations.

This invention provides compositions and methods to meet these needs. Inpreferred embodiments, the methods entail coating the surface to beprotected (e.g., surface of a car or truck or the walls and/or floors ofa spray booth) with a temporary protective coating composition asdescribed herein. One or more coating (e.g., painting) operations,and/or mechanical/handling operations are performed and, when desired,the protective composition is removed (e.g., by a simple water wash).

The coating compositions of this invention, when applied to a surface(e.g., the surface of an automobile), typically produce a substantiallycontinuous dry film that adheres well to the underlying surface. By“substantially continuous film” it is intended to mean herein a filmgenerally lacking pinholes through which, oil, paint, dust, or othermaterials could reach the underlying surface. Further, the material canbe removed easily from the surface to be protected after use with awater wash, or by mechanical means, or by combinations of these methods.In addition, because the material is biodegradable, it may be simplydisposed of (e.g., washed down a sewer) with no substantialenvironmental impact.

It was surprising discovery that thickeners, more preferably thixotropicthickeners, can act as effective film formers and provide significantprotection during a painting or other overcoating operation without theuse of other film formers. Moreover, it was discovered that extremelythin films can be applied (e.g., ˜0.06 mil) and still afford goodprotection to the underlying surface. Consequently material costs arereduced, and less effluent is produced in a given painting (overcoating)operation thereby reducing environmental impact.

When formulated as described herein, the thickener-based maskingcompositions provide effective protection of an underlying surfaceagainst paint spray, mechanical insult, and the like. It was aparticularly surprising discovery of this invention that the coatingsdescribed herein, can be applied to a painted automobile surface,effectively protect the underlying surface during a commercial paintingoperation (e.g., spray painting, temperature cycling, etc.), and areeasily washed off leaving the underlying surface in pristine condition.

A preferred method of protecting surfaces according to this inventionincludes steps of applying the coating compositions to the surface to beprotected in a substantially continuous film. The compositions are thendried to form a coating that protects the underlying surface from thecoating operation (e.g., paint overspray). The coating may besubsequently removed from the surface by simply washing with water whenit is longer required. In a particularly preferred embodiment, thecoatings of the present invention are used to protect components ofmotor vehicles (e.g., automobiles or automobile surface finishes), andthe walls and floors of spray booths or other areas or structures thatmay be contacted with overspray in a coating (e.g., painting) operation.

While in certain embodiments, the coating composition is dried beforeapplying an overcoating material (e.g., paint) to the surface, it was asurprising discovery that the coating composition can also prevent orgreatly diminish overspray (e.g., paint overspray) from sticking to thesurface while the coating composition is still wet. This permits if needbe, the user to move forward in the painting process without waiting forthe coating composition to dry. Previous technology has either notprevented overspray damage when wet, or the coating never became drywhich resulted in a messy repair environment.

In certain preferred embodiments, the masking compositions comprise anaqueous solution of a thickener (e.g., a thixotropic thickener) and a pHcontrol agent. The compositions can additionally include one or moreadditional components, including, but not limited to surfactant(s),alcohol(s), corrosion inhibitor(s), humectant(s), viscosity control(s),biocides, dyes/colorants, and the like, as described herein. Variouscomponents and ranges for illustrative formulations are shown in FIG. 1.Note these ranges and values are intended to be illustrative and notnecessarily limiting.

The aqueous masking compositions are formulated by simple mixing of thevarious components. It is noted, that when a component is referred to as“X weight percent active ingredient of a masking composition” this isreferred to as the weight percent of the active ingredient of thecomponent in the “final” masking composition before drying. Thus, forexample a commercial formulation of the thickener EP-1 consists of about30 weight percent active ingredient. When the masking compositioncomprises 4 weight percent of this formulation, the final activeingredient weight percent is 1.2 weight percent (0.3×0.04=0.012).

I. Thickener.

It was a surprising discovery that thickeners, in particular thixotropic(shear-thinning) thickeners, can act as film formers and, when used assuch, are capable of preventing penetration of a coating material (e.g.,paint) to an underlying surface (e.g., the surface as a vehicle). Inaddition, it was also a surprising discovery that an extremely thinbuild of such thickeners (e.g. 0.06 mil) provide a masking film thatoffers highly effective protection to the underlying surface duringcoating operations (e.g., during painting operations).

Thixotropic thickeners are known to those of skill in the art. Suchthickeners include, but are not limited to organowaxes (e.g., polylamidebased organowaxes, castor oil derivatives, etc.), associative thickeners(e.g., hydrophobically modified anionic soluble emulsions (HASEs),hydrophobically modified ethylene oxyde urethane rheology modifiers(HEURs), hydrophobically modified polyethers, etc.), and the like.Thixotropic thickeners are commercially available (e.g. TIXOGEL®, Noveon(formerly B.F. Goodrich) EP-1, Albucril ESP, PURE THIX™ thickeners,VERTEC AT™ thickeners, SOLTHIX™ thickeners, and the like).

Suitable thickeners for use in the present invention include, but arenot limited to neutralized cross-linked acrylate copolymers, neutralizedcross-linked polyacrylic acids, neutralized polyacrylic acids, algins,carboxymethylcellulose, neutralized polymethacrylic acids, neutralizedethylene-acrylic acid copolymers, methocel, gum arabic, cellulose gum,neutralized styrene acrylic acid copolymers, and combinations thereof.

In certain preferred embodiments, the thickeners include Noveon EP-1,and/or B.F. Goodrich Albucril ESP.

The thickener typically comprises from about 0.5 to about 10 weightpercent, preferably from about 1 to about 5 weight percent, morepreferably from about 1 to about 3 weight percent, and in someembodiments about 1.2 weight percent active ingredient of the aqueousmasking composition.

II. pH Control.

In certain embodiments, the masking compositions of this inventionadditionally, and optionally include a pH control. Suitable pH controlsinclude essentially any material that can be used to adjust the pH ofthe masking composition without damaging the surface that the maskingcomposition is applied to. The pH control can be provided as a buffer,and/or as a strong or weak acid, and/or as a strong or weak base.

In certain preferred embodiments the pH control is a basic pH controland is used to adjust the pH of the masking composition a range fromabout pH 7 to about pH 9.8, preferably from about pH 7.5 to about pH9.5, more preferably from about pH 8 to about pH 9.

In certain embodiments, the pH control agent comprises one or more basesincluding, but not limited to, sodium hydroxide, potassium hydroxide,magnesium hydroxide, an amine, and sodium bicarbonate.

III. Surfactant.

To provide a continuous and level film, the masking compositionpreferably adequately wets the surface to be protected. However, manysurfaces, in particular, car body finishes, are themselves highlyhydrophobic or purposely treated (e.g., waxed) to have a low surfacefree energy so that water will bead.

In a number of embodiments, a surfactant is not required, particularlywhere the surface to be protected (covered) is clean/pristine. Where theunderlying surface is less clean/pristine, however, effective maskingcan be facilitated by the incorporation of one or more surfactants intothe masking composition.

Suitable surfactants include, but are not limited to anionic surfactants(e.g., alkyl sulfates (e.g., RHODAPON™), ether sulfates (e.g.,RHODAPEX™), sulfonates (e.g., RHODACAL™), dodecylbenzene sulfonates,alpha-olefin sulfonates, diphenyl oxide disulfonates, phosphate esters(e.g., RHODAFAC™), carboxylates (e.g., Miranate™), etc.), cationicsurfactants (e.g., imidazolines (e.g., MIRAMINE™), ethoxylated amines(e.g., RHODAMEEN™, etc.), non-ionic surfactants (e.g., nonylphenolethoxylates (e.g., Igepal CO series), octylphenol ethoxylates (e.g.,Igepal CA series), nonionic esthers (e.g., Alkamuls™), oleyl alcoholethoxylates (e.g., RHODASURF™), ethoxylated mercaptans (e.g., ALCODET™),capped ethoxylates (e.g., ANTAROX™), blocked polymers, etc.), andamphoteric surfactants (e.g., imidazoline derivatives (MIRANOL™), fattyamine derivatives (e.g., MIRATAINE™), etc.). In certain preferredembodiments, the masking composition includes nonionic alkyl arylsurfactants such as Triton CF-10 and CF-12 (Rohm & Haas, Philadelphia,Pa., U.S.A.). Also suitable is Triton X-100 and surfactants havingfluorinated alkyl chains such as “Fluorad” products sold by MinnesotaMining and Manufacturing (St. Paul, Minn., U.S.A.) and “Zonyl” productssold by DuPont Company (Wilmington, Del., U.S.A.) are also suitable. Inaddition, many embodiments include polyethoxy adducts or modified(poly)ethoxylates such as Triton DF-12 and DF-16 sold by Union Carbide(Danbury, Conn., U.S.A.). Other surfactants includenonylphenoxypolyethanol (such as IGEPAL CO-660 made by GAF),polyoxyalkylene glycol (such as Macol 18 and 19 made by MazerChemicals), acetylenic diol-based surfactants (such as Surfynol 104Amade by Air Products), and the like.

One role the surfactant in the masking composition is facilitate wettingof the substrate (the underlying surface) by the masking compositionthereby leading to the formation of a continuous film. In certainembodiments, a sufficiently continuous protective film could be obtainedwith little or no surfactant so long as underlying surface issufficiently clean and/or the masking composition contains a sufficientsolids content (e.g., thickener) to produce a substantially continuousfilm. Films containing high solids concentrations are often highlyviscous and therefore difficult to apply, especially by spraying. Theuse of surfactants or other wetting agents is preferred as coatingscontaining surfactants show superior film-forming properties in avariety of application methods even where solids content is quite low.

In certain embodiments, the wetting properties of the coatingcompositions may be improved by adding certain surfactant compositions,and/or by adding various water soluble alcohols such as propanol,methanol, or isopropyl alcohol, or by adding aliphatic polyols such aswater soluble alcohols up to octanol. In particularly preferredembodiments, surfactants are used in the masking compositions of thepresent invention.

Certain preferred surfactants for use in the masking compositions of thepresent invention should reduce the surface tension of the maskingcomposition to a sufficiently low value that a level film, free ofpinholes, is laid down. In certain embodiments, the surfactant willreduce the surface tension of the masking composition to at most about25 dynes per centimeter, and more preferably to at most about 20dyne/cm. To avoid formation of pinholes, the surfactant should not foam.

In addition, surfactants are preferably selected that work with avariety of surfaces such as those containing silicones, acrylic waxes,teflon® waxes, clear coats, natural and hydrocarbon waxes, etc. Stillfurther preferred surfactants will be relatively inexpensive, willprovide a product that does not spot, streak, or frame (i.e., evaporatefaster at edges such as molding and/or trim) on the surface to beprotected. Finally, the surfactant is preferably water soluble andotherwise compatible with the other components of the maskingcomposition so that the composition does not separate and leave pinholeswhen dry.

Because many surfaces to be protected will have unusually low surfacefree energies, in many embodiments, surfactans are selected that areable to dramatically lower the surface and interfacial tensions of themasking composition. Compositions having very low surface tensions alsotend to produce many fewer pinholes in the coating. Thus, any of theknown classes of very low surface tension surfactants are preferred foruse in certain embodiments of this invention.

One such class is the alkoxylates of fluorinated alkyl chains. Otherfunctional derivatives (e.g., esters, sulfonates, carboxylates, ammoniumcompounds, etc.) of fluorinated alkyl chains also tend to produce lowsurface tension aqueous solutions. In general, replacement of hydrogenson an alkyl group by fluorine atoms leads to surfactants of unusuallylow surface tension. The above mentioned “Fluorads” and “Zonyls” areexamples of surfactants having fluorinated alkyl chains.

Various embodiments, contemplate the use of combined surfactants. Forexample, in certain embodiments, fluorinated surfactants can be combinedwith sulfonated surfactants or various non-ionic surfactants.

It has been discovered that a in certain particularly preferredembodiments the surfactants include one or more non-ionic surfactants.Certain preferred surfactants include alcohol ethoxylates (e.g.,TOMADOL™ 91-6. On preferred surfactant includes TOMADOL™ 91-6 andTriton™ DF-16.

The surfactant is typically present in an amount effective to produce acoating that lays out smoothly in a substantially continuous film of thepainted surface of an automobile. In certain embodiments, preferredmasking compositions include up to 5 percent surfactant, preferably upto about 3 percent surfactant, still more preferably up to about 1percent surfactant and most preferably up to about 0.5 or 0.3 percentsurfactant.

IV. Alcohol.

In certain embodiments, the masking compositions of this inventionoptionally include a water soluble alcohol. The alcohol can act as adrying agent to speed drying of the film, as a wetting agent, and as abiocide/preservative.

Suitable alcohols include, but are not limited to various straight chainalcohols (e.g., propanol, methanol, ethanol, etc.) and/or variousaliphatic polyols such as water soluble alcohols up to octanol. Thealcohol(s), when present, are typically present in a range from about 0weight percent to about 20 weight percent, preferably from about 0.1weight percent to about 10 weight percent, more preferably from about0.2 weight percent to about 5 weight percent, and most preferably fromabout 3 to about 4 weight percent active ingredient of the maskingcomposition.

V. Preservative/Biocide.

The constituents of the coating compositions of this invention can, incertain instances, support the growth of microorganisms such asmicrobes, fungi, and the like. Thus, in certain embodiments, to increasestorage life, it is desired to include a preservative. The term“preservative”, as used herein, is intended to designate a substanceshowing antimicrobial properties, in particular bactericidal propertiesand preferably also antifungal properties. Preservatives are well knownto those of skill in the art and include, but are not limited toanti-bacterial agents, anti-fungal agents, bacteriostatic agents,fungistatic agents, and enzyme inhibitors. Suitable preservativesinclude, but are not limited to benzoic acid, sorbic acid or the saltsthereof, thimerosal (or merthiolate), phenyl mercuric acetate, phenylmercuric nitrate, detergents (e.g., benzalkonium chloride), and sodiumazide. Preferred preservatives are relatively or completely non-toxic tohigher animals (e.g., mammals) and, thus, preservatives commonly used infoodstuffs and medical products are suitable. Such preservativesinclude, but are not limited to ethyl alcohol, chlorhexidine gluconate,sorbic and benzoic acid and their salts, and the like. Other preferredpreservatives include Kathon LX (Rohm Haas, Inc.) and BTC 2125 (StephanChemical Co., Inc.).

The preservatives, when present, typically range from about 0 weightpercent up to about 0.2 weight percent, preferably from about 0.01weight percent, up to about 0.005 weight percent.

VI. Viscosity Control.

The masking compositions of this invention can optionally include one ormore viscosity control agents. The viscosity control agents aretypically selected to adjust the viscosity for a particular applicationmethods (e.g., brushing, doctor bar, spraying, etc.). Viscosity controlagents are well known to those of skill in the art.

In certain embodiments, salts provide effective viscosity control agentsand can effectively be used to “thin” the thixotropic thickeners used inthe compositions of this invention.

Suitable salts include, but are not limited to, sulfates (e.g., sodiumsulfate, potassium sulfate, etc.), chlorides (e.g., sodium chloride,potassium chloride), bromides (e.g., sodium bromide, potassium bromide),and the like. In certain embodiments, the salt is sodium sulfate.

When present the salt typically ranges from about 0 to about 2 weightpercent, preferably from about 0.1 to about 1 weight percent, and morepreferably from about 0.1 to about 0.5 weight percent active ingredientof the masking composition.

VII. Flash Corrosion Inhibitor.

The masking compositions of this invention can optionally include one ormore “flash corrosion inhibitors” (“flash rust inhibitors). Flashcorrosion inhibitors compatible with aqueous systems are well known tothose of skill in the art. Such inhibitors include, but are not limitedto ammonium benzoate, ADD APT® Ferrocor flash corrosion inhibitor,M-435, M-240, alkyl alkanolamines (e.g., MORLEX™), and the like. INcertain embodiments, the flash corrosion inhibitor comprises ammoniumbenzoate.

When present, the flash corrosion inhibitor typically ranges from about0 to about 0.5 weight percent, preferably from about 0.1 weight percentto about 0.2 weight percent active ingredient in the maskingcomposition.

VIII. Humectant.

The masking compositions of this invention can optionally include one orhumectants. Humectants are well known to those of skill in the art.Certain preferred humectants include glycols (e.g., polyethylene glycol400), and the like.

Certain other humectants provide more environmentally friendlyalternatives to traditional humectants. Thus, for example, humectantGRB2 is an 80% aqueous solution of a non-ionic dispersant mixed with lowmolecular weight polyols, which is supplied as a straw colored liquidand contains minimal VOCs.

When present, a humectant ranges from about 0 weight percent to about 5weight percent, preferably from about 0.01 weight percent to about 1 or2 weight percent, more preferably from about 0.1 weight percent to about0.5 weight percent active ingredient in the masking composition.

IX. Dye/Coloring Agent.

The composition can additionally include dyes or color agents, scents,and the like. In certain embodiments that dyes range from about 0 weightpercent up to about 0.05 weight percent, preferably from about 0.01 0.02weight percent active ingredient in the masking composition.

X. Sugar.

In various embodiments, the masking composition can additionally includeone or more sugars. It has been observed that the sugar is beneficial inhelping the coating to more completely release from the underlyingsurface (prevent crosslinking). Suitable sugars include, but are notlimited to sucrose, glucose, fructose, corn syrup, sorbitol, glycerin,and the like. In certain embodiments, glucose (as opposed to saysorbitol) is used because can be less “sticky” and therefore more usefulin a coating that gets touched.

EXAMPLES

The following examples are offered to illustrate, but not to limit theclaimed invention.

Example 1

To produce various surface protective coatings, of this invention,components (as shown in Table 1) were combined at room temperature andat atmospheric pressure by slow stirring to form the various surfaceprotective coating compositions shown in Table 1. The homogeneouscoating compositions were then adjusted to 8.5-9.5 by the addition ofsodium hydroxide. TABLE 1 One illustrative formulation of the maskingcomposition. % Active % Active Typical Ingredient % Component Ingredientin Commercial In Unit in Masking Masking Component Form (% A.I.)Material Material Min Max Thickener/ Carbopol EP-1 30 4.000 1.200 0.5 10Film Former Noveon Humectant Polyethylene 100 0.100 0.100 0 5 Glycol 400Flash Ammonium 100 0.010 0.010 0 0.5 Corrosion Benzoate InhibitorViscosity Sodium Sulfate 100 0.100 0.100 0 2 Control pH control Sodium100 0.175 0.175 0.02 0.5 Hydroxide Surfactant Tomadol 91-6 100 0.2500.250 0 5 Primary Tomah Surfactant Triton DF-16 100 0.025 0.025 0 5Secondary Union Carbide Biocide Kathon LX 14 14 0.01 0.0014 0 0.01 Rohm& Haas Dye/Coloring Uranine 75 0.010 0.0075 0 0.02 Abbey Water Deionized100 Remainder Remainder Remainder Remainder

It is understood that the examples and embodiments described herein arefor illustrative purposes only and that various modifications or changesin light thereof will be suggested to persons skilled in the art and areto be included within the spirit and purview of this application andscope of the appended claims. All publications, patents, and patentapplications cited herein are hereby incorporated by reference in theirentirety for all purposes.

1. A method of temporarily protecting a surface in a coating operation,said method comprising: a) applying a masking material to said surface,said applying resulting in a dry substantially continuous film of saidmasking material, said masking material, before drying, comprising anaqueous solution of: i) a thixotropic thickener present in an amountranging from about 0.15 to about 5 weight percent active ingredient; andii) a pH control to adjust pH of said masking material from about pH 7.5to about pH 9.5; b) coating all or a portion of said surface with anovercoating compound, said masking material preventing said coatingcompound from contacting said surface; and c) removing said maskingmaterial from said surface whereby the coating compound applied to thesurface covered with the masking material is removed together with themasking material.
 2. The method of claim 1, wherein said coating isperformed before said masking material is dried.
 3. The method of claim1, wherein said coating is performed after said masking material isdried.
 4. The method of claim 1, wherein said overcoating compound ispaint.
 5. The method of claim 1, wherein said surface is a surface of avehicle.
 6. The method of claim 1, wherein said surface is a surface ofan automobile.
 7. The method of claim 1, wherein said surface comprisesa painted surface of an automobile.
 8. The method of claim 1, whereinsaid surface comprises a bumper or trim of a vehicle.
 9. The method ofclaim 1, wherein said thixotropic thickener is a thickener selected fromthe group consisting of Carbopol™ EP-1, and Albucril ESP.
 10. The methodof claim 1, wherein said pH control comprises a base.
 11. The method ofclaim 1, wherein said pH control comprises a base selected from thegroup consisting of sodium hydroxide, potassium hydroxide, magnesiumhydroxide, an amine, and sodium bicarbonate.
 12. The method of claim 1,wherein said masking material further comprises a surfactant.
 13. Themethod of claim 12, wherein said masking material further comprises asurfactant present in an amount effective to produce a coating that laysout smoothly in a substantially continuous film of the painted surfaceof an automobile.
 14. The method of claim 12, wherein said surfactant ispresent at less than about 1 weight percent active ingredient of saidmasking material.
 15. The method of claim 12, wherein said surfactantcomprises a non-ionic surfactant.
 16. The method of claim 15, whereinsaid surfactant comprises an alcohol ethoxylate.
 17. The method of claim15, wherein said surfactant comprises TOMADOL™ 91-6 and TRITON™ DF-16.18. The method of claim 1, wherein said masking material furthercomprises a viscosity control.
 19. The method of claim 18, wherein saidviscosity control is a salt.
 20. The method of claim 18, wherein saidviscosity control comprises sodium sulfate.
 21. The method of claim 18,wherein said viscosity control ranges up to about 2.0 weight percentactive ingredient of said masking material.
 22. The method of claim 1,wherein said masking material further comprises an alcohol.
 23. Themethod of claim 22, wherein said alcohol is a straight chain alcohol.24. The method of claim 22, wherein said alcohol is selected from thegroup consisting of ethanol, methanol, and propanol.
 25. The method ofclaim 22, wherein said alcohol is present in a concentration ranging upto about 20 weight percent active ingredient of said masking material.26. The method of claim 1, wherein said masking material furthercomprises a biocide.
 27. The method of claim 26, wherein said biocideranges up to about 0.2 weight percent active ingredient of said maskingmaterial.
 28. The method of claim 28, wherein said biocide comprisesKathon LX
 14. 29. The method of claim 1, wherein said masking materialfurther comprises a humectant.
 30. The method of claim 29, wherein saidhumectant ranges up to about 5 weight percent active ingredient of saidmasking material.
 31. The method of claim 29, wherein said humectantcomprises polyethylene glycol.
 32. The method of claim 1, wherein saidmasking material further comprises a flash corrosion inhibitor.
 33. Themethod of claim 32, wherein said flash corrosion inhibitor comprises upto about 0.01 weight percent active ingredient of said masking material.34. The method of claim 32, wherein said flash corrosion inhibitorcomprises ammonium benzoate.
 35. The method of claim 1, wherein saidmasking material further comprises: a surfactant; a flash corrosioninhibitor; a viscosity control; an alcohol; and a humectant.
 36. Themethod of claim 35, wherein: said thixotropic thickener ranges fromabout 0.1 to about 10 weight percent active ingredient of said maskingmaterial; said pH control is sufficient to set the pH of said maskingabout pH 7.5 to about pH 9.5; said surfactant comprises less than about1 weight percent active ingredient of said masking material; said flashcorrosion inhibitor comprises from about 0 to about 0.2 weight percentactive ingredient of said masking material; said viscosity controlcomprises a salt ranging from about 0 to about 2 weight percent activeingredient of said masking material; said alcohol comprises from about 0to about 20 weight percent active ingredient of said masking material;and said humectant comprises from about 0 to about 5 weight percentactive ingredient of said masking material.
 37. The method of claim 36,wherein: said thixotropic thickener is EP-1; said pH control is sodiumhydroxide; said surfactant is a nonanionic surfactant; said flashcorrosion inhibitor is ammonium benzoate; said viscosity control agentis sodium sulfate; said alcohol is ethanol; and said humectant ispolyethylene glycol.
 38. The method of claim 37, wherein: saidthixotropic thickener ranges from about 1 to about 2 weight percentactive ingredient of said masking material; said pH control issufficient to set the pH of said masking about pH 8.5 to about pH 9.5;said surfactant comprises less than about 0.5 weight percent activeingredient of said masking material; said flash corrosion inhibitorcomprises less than about 0.01 weight percent active ingredient of saidmasking material; said viscosity control comprises less than about 0.15weight percent active ingredient of said masking material; said alcoholcomprises less than about 0.4 weight percent active ingredient of saidmasking material; and said humectant comprises less than about 0.15weight percent active ingredient of said masking material.
 39. A maskingcomposition for the temporary protection of a surface during a coatingprocedure, said masking composition comprising an aqueous solution of:i) a thixotropic thickener present in an amount ranging from about 0.15to about 5 weight percent active ingredient of said masking composition;and ii) a pH control to adjust pH of said masking composition from aboutpH 7.5 to about pH 9.5.
 40. The composition of claim 39, wherein saidthixotropic thickener is a thickener selected from the group consistingof CARBOPOL™ EP1, and Albucril ESP.
 41. The composition of claim 39,wherein said pH control comprises a base.
 42. The composition of claim39, wherein said pH control comprises a base selected from the groupconsisting of sodium hydroxide, potassium hydroxide, magnesiumhydroxide, an amine, and sodium bicarbonate.
 43. The composition ofclaim 39, wherein said masking composition further comprises asurfactant.
 44. The composition of claim 39, wherein said maskingcomposition further comprises a surfactant present in an amounteffective to produce a coating that lays out smoothly in a substantiallycontinuous film of the painted surface of an automobile.
 45. Thecomposition of claim 44, wherein said surfactant is present at less thanabout 1 weight percent active ingredient of said masking material. 46.The composition of claim 44, wherein, wherein said surfactant comprisesa non-ionic surfactant.
 47. The composition of claim 46, wherein,wherein said surfactant comprises an alcohol ethoxylate.
 48. Thecomposition of claim 46, wherein said surfactant comprises TOMADOL™ 91-6and TRITON™ DF-16.
 49. The composition of claim 39, wherein said maskingcomposition further comprises a viscosity control.
 50. The compositionof claim 49, wherein said viscosity control is a salt.
 51. The method ofclaim 49, wherein said viscosity control comprises sodium sulfate. 52.The method of claim 49, wherein said viscosity control ranges up toabout 2.0 weight percent active ingredient of said masking composition.53. The composition of claim 39, wherein said masking compositionfurther comprises an alcohol.
 54. The composition of claim 53, whereinsaid alcohol is a straight chain alcohol.
 55. The composition of claim53, wherein said alcohol is selected from the group consisting ofethanol, methanol, and propanol.
 56. The composition of claim 53,wherein said alcohol is present in a concentration ranging up to about20 weight percent active ingredient of said masking material.
 57. Thecomposition of claim 39, wherein said masking composition furthercomprises a biocide.
 58. The composition of claim 57, wherein saidbiocide ranges up to about 0.2 weight percent active ingredient of saidmasking composition.
 59. The composition of claim 57, wherein saidbiocide comprises Kathon LX
 14. 60. The composition of claim 39, whereinsaid masking composition further comprises a humectant.
 61. Thecomposition of claim 60, wherein said humectant ranges up to about 5weight percent active ingredient of said masking composition.
 62. Thecomposition of claim 60, wherein said humectant comprises polyethyleneglycol.
 63. The composition of claim 39, wherein said maskingcomposition further comprises a flash corrosion inhibitor.
 64. Thecomposition of claim 63, wherein said flash corrosion inhibitorcomprises up to about 0.01 weight percent active ingredient of saidmasking composition.
 65. The composition of claim 63, wherein said flashcorrosion inhibitor comprises ammonium benzoate.
 66. The composition ofclaim 39, wherein said masking material further comprises: a surfactant;a flash corrosion inhibitor; a viscosity control; an alcohol; and ahumectant.
 67. The composition of claim 66, wherein: said thixotropicthickener ranges from about 0.1 to about 10 weight percent activeingredient of said masking composition; said pH control is sufficient toset the pH of said masking about pH 7.5 to about pH 9.5; said surfactantcomprises less than about 1 weight percent active ingredient of saidmasking composition; said flash corrosion inhibitor comprises from about0 to about 0.2 weight percent active ingredient of said maskingcomposition; said viscosity control comprises a salt ranging from about0 to about 2 weight percent active ingredient of said maskingcomposition; said alcohol comprises from about 0 to about 20 weightpercent active ingredient of said masking composition; and saidhumectant comprises from about 0 to about 5 weight percent activeingredient of said masking composition.
 68. The composition of claim 67,wherein: said thixotropic thickener is EP-1; said pH control is sodiumhydroxide; said surfactant is a nonionic surfactant; said flashcorrosion inhibitor is ammonium benzoate; said viscosity control agentis sodium sulfate; said alcohol is ethanol; and said humectant ispolyethylene glycol.
 69. The composition of claim 68, wherein: saidthixotropic thickener ranges from about 1 to about 2 weight percentactive ingredient of said masking composition; said pH control issufficient to set the pH of said masking about pH 8.5 to about pH 9.5;said surfactant comprises less than about 0.5 weight percent activeingredient of said masking composition; said flash corrosion inhibitorcomprises less than about 0.01 weight percent active ingredient of saidmasking composition; said viscosity control comprises less than about0.15 weight percent active ingredient of said masking composition; saidalcohol comprises less than about 0.4 weight percent active ingredientof said masking composition; and said humectant comprises less thanabout 0.15 weight percent active ingredient of said masking composition.70. A kit for temporarily protecting a surface, said kit comprising: acontainer containing a masking material according to any of claims 39 to69; and instructional materials teaching the use of said maskingcomposition for temporarily protecting a surface during an overcoatingoperation or during mechanical handling.
 71. Advertising materialscomprising an audio or audiovisual presentation teaching the use of acontainer containing a masking material according to any of claims 39 to69 in a painting operation.
 72. The advertising materials of claim 71,wherein said audio or audiovisual presentation comprises a mediumselected from the group consisting of an audio tape, a compact disk, avideo tape, a DVD, a view master, a slide show, an mpeg file, and apowerpoint presentation.
 73. An article of manufacture comprising one ormore surfaces coated with a masking composition, said composition,before drying being a masking composition according to any of claims 39to
 69. 74. The article of manufacture of claim 73, wherein said articleof manufacture is an automobile or a component of an automobile.